Analog-to-digital converters (ADC) have a variety of uses in applications relating to signal processing in various fields, for example, in processing relating to image, video, audio, data storage and retrieval.
A typical ADC may have a pipeline structure with multiple sample-and-hold or track-and-hold (T/H) circuits in multiple stages, which enables the ADC to process signals in discrete-time through the stages. As bandwidth requirement of the ADC increases to include higher frequencies in newer applications, the sampling rate of the ADC is also increased. Consequently, the high speed at which the T/H circuits need to settle may limit the conversion speed of the ADC. Additionally, the multiple T/H circuits and their clock drivers may take up valuable circuitry space and increase power consumption.
Thus, there is a need for improved ADC's that reduces T/H circuits by performing signal processing in continuous-time forms to decrease cost and power requirements while improving performance.